From b2f56462d51a49c28d2a7b214b3ae8e8d3329f1f Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Tue, 8 Mar 2016 12:44:52 +0800 Subject: [PATCH] backup: Use Bitmap to replace "s->bitmap" "s->bitmap" tracks done sectors, we only check bit states without using any iterator which HBitmap is good for. Switch to "Bitmap" which is simpler and more memory efficient. Meanwhile, rename it to done_bitmap, to reflect the intention. Signed-off-by: Fam Zheng Reviewed-by: John Snow Message-id: 1457412306-18940-2-git-send-email-famz@redhat.com Signed-off-by: Max Reitz --- block/backup.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/block/backup.c b/block/backup.c index 0f1b1bc084..ab3e345e92 100644 --- a/block/backup.c +++ b/block/backup.c @@ -20,6 +20,7 @@ #include "qapi/qmp/qerror.h" #include "qemu/ratelimit.h" #include "sysemu/block-backend.h" +#include "qemu/bitmap.h" #define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16) #define SLICE_TIME 100000000ULL /* ns */ @@ -42,7 +43,7 @@ typedef struct BackupBlockJob { BlockdevOnError on_target_error; CoRwlock flush_rwlock; uint64_t sectors_read; - HBitmap *bitmap; + unsigned long *done_bitmap; int64_t cluster_size; QLIST_HEAD(, CowRequest) inflight_reqs; } BackupBlockJob; @@ -116,7 +117,7 @@ static int coroutine_fn backup_do_cow(BlockDriverState *bs, cow_request_begin(&cow_request, job, start, end); for (; start < end; start++) { - if (hbitmap_get(job->bitmap, start)) { + if (test_bit(start, job->done_bitmap)) { trace_backup_do_cow_skip(job, start); continue; /* already copied */ } @@ -167,7 +168,7 @@ static int coroutine_fn backup_do_cow(BlockDriverState *bs, goto out; } - hbitmap_set(job->bitmap, start, 1); + set_bit(start, job->done_bitmap); /* Publish progress, guest I/O counts as progress too. Note that the * offset field is an opaque progress value, it is not a disk offset. @@ -399,7 +400,7 @@ static void coroutine_fn backup_run(void *opaque) start = 0; end = DIV_ROUND_UP(job->common.len, job->cluster_size); - job->bitmap = hbitmap_alloc(end, 0); + job->done_bitmap = bitmap_new(end); bdrv_set_enable_write_cache(target, true); if (target->blk) { @@ -480,7 +481,7 @@ static void coroutine_fn backup_run(void *opaque) /* wait until pending backup_do_cow() calls have completed */ qemu_co_rwlock_wrlock(&job->flush_rwlock); qemu_co_rwlock_unlock(&job->flush_rwlock); - hbitmap_free(job->bitmap); + g_free(job->done_bitmap); if (target->blk) { blk_iostatus_disable(target->blk);